Power-driven cast cutter



s P 1950 A. a. WILCQX 2,522,006

' POWER-DRIVEN CAST cu'r'rsa- I Filedllay 31, 1946 1415+ E Wzcox Patented Sept. 12, 1950 I UNITED STATES PATENT OFFICE 4 Claims.

This invention relates to a. cast cutter for cutting or sawing plaster casts from patients who have been injured and who have had such casts applied.

An object of the invention is to provide a cast cutter in the nature of a power-driven circular saw which is so protected by means of guards that the cast cutter may be applied to the cast to quickly saw through the same without danger of injuring the patient.

Another object of the invention is to provide a cast cutter in the form of a suitably guarded or protected circular saw that is power-driven and to provide means for withdrawin the cuttings produced by the saw in the course of cutting the cast.

Still another object of the invention is to provide a cast cutter which is so constructed and so designed that it will effectively cut through not only the plaster of a plaster cast but also through sheet wadding and stockinet that are conveniently employed as parts of the cast.

With the foregoing and other objects in view, which will be made manifest in the following detailed description and specifically pointed out in the appended claims, reference is had to the accompanying drawings for an illustrative embodiment of the invention, wherein:

Figure 1 is a top plan view of the improved cast cutter embodying the present invention;

Fig. 2 is a view in side elevation of the same taken. substantially in the direction of the arrow 2 upon Fig. 1.

Fig. 3 is a view in front elevation of the cast cutter, parts being broken away and shown in vertical section, and

Fig. 4 is a partial view in vertical section taken substantially upon the line 4-4 upon Fig. 2.

Referring to the accompanying drawings wherein similar reference characters designate similar parts throughout, the improved cast outter comprises an electric motor the housing of which is indicated at H] and which is preferably provided with a pistol grip II on which there is a finger switch I2 that controls the supply of electric current to the motor such as through a cord 13. The rotor of the motor drives through a reduction gear box M to a rotary spindle l5 that is rotatably mounted in a hub or frame it secured to the gear box. The hub or frame has an upstanding handle H at the bottom of which there is a forwardly extending horizontally disposed grooved guard l8 having a shallow groove I9 therein. Circular saws 20 are mounted on the spindle l5 so as to be rotated thereby and the 2 teeth of these saws are arranged to enter the groove l9 so as to just clear its bottom. The sides of the grooves may be slightly thickened as at 2 I so as to project upwardly a small distance .to assure that the saws on entering the groove will cut entirely through the plaster cast 0. The connection 22 between the back of the guard l8 and the bottom of the handle is sufficiently thin so as to pass through the saw cut produced by the rotating saws. On the hub or frame it there is a semi-circular guard 23 enclosing the upper portions of the saws and this semi-circular guard preferably has a hinged extension 24 that is secured to the semi-circular guard by a spring hinge 25 that normally urges the extension 24 downwardly into engagement with the cast. The semi-circular guard 28 has a groove 25 extending longitudinally thereof and this groove is con nected by means of a tube 21 to a vacuum pump or any suitable source of vacuum.

In removing a plaster cast from a patient the forward end of the guard 18 is inserted between the cast and the body of the patient. The downwardly urged extension 24 is positioned on top of the cast and serves to confine some of the cuttings. In this position the cast cutter is advanced forwardly while the saws are rotated by the vmotor l0 and cut through the entire cast. The guard It being interposed beneath the bottoms of the saws efiectively prevents the saws from cutting the patient but as the saws enter the shallow groove l9 they will be caused to out completely through the cast. As the cast cutter is advanced the thin connection 22 which is thinner than the combined width of the saws merely passes through the saw cut. During the cutting operation the cuttings are largely confined within the guard 23 and the extension 24 and are continuously withdrawn by means of the vacuum supplied through the tube 21.

It will be appreciated from the above described construction that a cast may be quickly and easi, ly out without danger of injuring the patient or requiring any great deformation of the body of the patient inasmuch as the guard l8 that is interposed between the cast and the body is relatively thin.

I find that it is of advantage to use three saws in side-by-side relationship with the outer saw particularly having their teeth out with considerable clearance. If a single saw is employed my experience has been that the sheet wadding and stockinet tend to ball up and jam between the saw and the sides of the saw cut. However, when three saws are positioned side-by-side with the teeth on the outer saw providing adequate clearance I am able to cut through plaster casts and through sheet wedding and stockinet without difiiculty.

From the above-described construction it will be appreciated that an improved cast cutter is provided which will enable a plaster cast to be out quickly and easily with a minimum amount of discomfort to the patient.

Various changes may be made in the details of construction without departing from the spirit and scope of the invention as defined by the appended claims.

I claim:

1. A cast cutter comprising a power-driven circular saw, a vertical handle having an upper grasping portion and a lower supporting portion for advancing the circular saw, a guard disposed adjacent the bottom of the circular saw formed integral with the lower supporting portion of the handle. at approximately. right angles thereto, a semicircular guard extending from the lower supporting portion of the handle and fixedly mounted thereon and enclosing the upper portion of the circular saw, and-means for withdrawing cuttings through the guard for the upper portion of the saw, the guard for the upper portion of the saw having an extension at the forward end thereof hingedly connected thereto, and means for urging the extension toward the saw.

2, A compact self-contained power-driven cast cuttercomprising a hub having a rotatable shaft mounted therein, a circular saw fixedly mounted on one end of the shaft, a reduction unit fixedly mounted on one end of the hub and connected to the other end of said shaft, a motor fixedly mounted on the reduction drive soas to drive said saw through the reduction unit, a Vertical handle having the lower portion thereof integral with the hub for advancing the circular saw, an imperforate guard formed integral with the lower portion-of the handle disposed adjacent the bottom of the circular Saw at approximately right angles to said handle, a semicircular guard integral, with the hub enclosing the upper portion of the circular saw and having a groove extending around the inner longitudinal surface thereof and leading to an outlet from said semicircular guard, and means for drawing cuttings through the outlet, the guard for the upper portion of the sawhaving an extension hinged to the forward end thereof by a spring hinge.

3;. A, cast cutter comprising a power-driven cir- 4 cular saw, a vertical handle having an upper grasping portion and a lower supporting portion for advancing the circular saw and for rotatably supporting the saw, a guard disposed adjacent the bottom of the circular saw fixedly secured to the lower supporting portion of the handle so as to extend therefrom at approximately right angles thereto, a semi-circular guard extending from the lower supporting portion of the handle and fixedly mounted thereon and enclosing the upper portion of the circular saw, means for withdrawing cuttings through the guard for the upper portion of the saw, a deflector guard swingably mounted on the forward end of the semi-circular guard for deflecting cuttings, and means for urging the deflector guard toward the casting to be cut.

4. A compact power driven cast cutter comprising a hub having a shaft rotatably mounted therein, a circular saw secured to one end of the shaft, a speed reduction unit secured to the hub and connected to the other end of the shaft to drive the same, a motor secured to the eduction unit and connected to the same for driving the; reduction unit, a vertical handle secured to the hub for advancing the circular saw, a guard fix.- edly secured to the lower end of the handle and extending beneath the saw at approximately right angles to the handle, a semi-circular guard secured to the hub enclosing the upper portion of the circular saw and having a groove extending around the interior thereof and leading to an outlet from said semi-circular guard, means for withdrawing cuttings through the outlet, an extension guard swingably mounted on the forward end of the semi-circular guard, and means for urging the extension guard toward the casting to be out,

.ALEX B.

ELEFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date- 389,006 Philp Sept. 4, 1888? 1,942,766 OBanion Jan. 9, 1934 2,139,272 Jaworski Dec; 6, 1938 2,232,733 Scarboro Feb. 25; 1941' 2,330,952 Christen et al. Oct. '5, 1943 2,344,262 Odierna et al Mar. 14, 1944 2,406,744 Cryar Sept. 3; 1946- 

